The present disclosure relates to a biopsy needle device to be used for sampling of biological tissue.
Biopsy needle devices are known that comprise an internal needle having a recess on the outer periphery near the tip, a cylindrical external needle fitting around the internal needle in a freely slidable manner in the lengthwise direction, an internal needle holding member that holds the base end section of the internal needle, an external needle holding member that holds the base end section of the external needle, an enclosure that houses the internal needle holding member and the external needle holding member in a free back-and-forth manner, a retracting device that retracts the internal needle holding member and the external needle holding member, an internal needle locking device that locks the retracted internal needle holding member at a prescribed trigger standby position, an external needle locking, device that locks the retracted external needle holding member at a prescribed trigger standby position, an unlocking operation device that unlocks the internal needle locking device and the external needle locking device in that order, an internal needle trigger spring that is energized in response to retraction of the internal needle holding member and triggers the internal needle in the forward direction in response to unlocking operation of the internal needle locking device, and an external needle trigger spring that is energized in response to retraction of the external needle holding member and triggers the external needle in the forward direction in response to unlocking operation of the external needle locking device, whereby triggering of the external needle accomplishes cutting and sampling of the biological tissue that has been drawn into the recess of the internal needle after triggering of the internal needle (see Japanese Published Examined Patent Application No. H6-28663, for example). This type of biopsy needle device allows sampling of biological tissue to be accomplished in a convenient manner simply by inserting the internal needle and external needle into the body and then carrying out triggering of the internal needle and triggering of the external needle in that order.